Electric motors (e.g., permanent magnet synchronous motors) are used in a variety of applications, including vehicle applications. In hybrid vehicle development, the electric motor is a fundamental component of the hybrid powertrain system. Among other functions, the electric motor is a torque source. For example, the motor may be operated to produce a positive torque for propelling the vehicle in a motoring mode. The motor may also be operated to produce a negative torque for energy generation in a generating mode.
The actual torque output of the electric motor may not necessarily correspond with a desired or commanded torque, and thus affect the torque integrity. For example, the electric motor may produce a torque output having a polarity that is opposite of the commanded torque. The commanded torque value may be compared with the actual torque output of the electric motor to determine whether a threshold is exceeded for control. However, a number of variables (e.g., measured motor speed, conditions contributing to losses, sensed rotor position, or the like) may affect the determination of the actual torque output.
Accordingly, it is desirable to provide a method and system for monitoring electric motor torque. Additionally, it is desirable to provide a method and system for detecting motor torque integrity of hybrid vehicles. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.